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<title>类选择器</title>
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<h2 class="green">静夜思</h2>
<p class="blue fontl">唐：李白</p>
<p class="green fontl">床前明月光，</p>
<p>疑是地上霜。</p>
<p>举头望明月，</p>
<p>低头思故乡。</p>
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